Protection of steel.



E. M. GAFPALL;

PROTECTION OF STEEL.

APPLICATION FILED OOT.15, i910.

WITNESSES messes. i

nnwaitn ma cArrALL, on sPAnKrcL, NEW YORK.

I P ROTECTIDN- OF STEEL.

Specification of Letters Patent.

Application filed October 15, 1910. Serial No. 587,184.

To all'whom it may concern:

Be it known that I, EDWARD M. CAFE-ALL,-

a cit-izen'of the United States, and resident of Sparkill, in the county of Rockland and State of New York, have invented certain new and useful Improvements in the Protection of Steel, of which the following is a specification.

My invention relates to a process for protecting steel products, particularly such as beamsand' rails, from corrosion or oxidation 'non-oxidizable metals are in vogue. The

corrosion is variously attributed to chemical and to electrical action. While plating processes are satisfactory to a certain degree they are very. expensive. Ordinary paint while effective to a certain extent is itself subject. to oxidation and readily flakes off and this leaves the surface of the metal exposedto local action. Y

It is my object to provide a method'for coating steel which is inexpensive and which will result in a permanent indestructible product.

My improved method contemplates immersing the steel while hot in a bath of paraflin then withdrawing the steel and allowing it to cool. The temperature of the bath should be about.150 F. or somewhat bers such as beams immediately after-they higher and the temperature of the steel con siderably higher but below 600 F. If the temperature is much higher than this the bath is likely to be ignited. The steel to be treated should be practically free from scale and for this reason'I prefer to treatmemleave the final finishing rolls of the mill and before scale forms. As they come from these rolls if thetemperature is above 600 F: they should be allowed to cool slightly. As they are plunged into the bath'the temperature of t e steel falls and the metal contracts. In this way the hot. parafiin' is drawn into the pores of the steel to a conand practically siderable extent and becomes so anchored that there is no tendency for it to peel off. The paraffin coat formed by more or less flexible so that the bending of the steel does not crack it off.

The temperastantially constant by suitable means. Preferably when the beams are withdrawn from the bath they are allowed to drain adjaadhering .to' the beams will run back into the bath. The drawing is a diagrammatic illustration of ap tioninto e products.

The reference numeral 1 indicates the final pair of finishing rolls of a mill. These are driven by any suitable source of power as for instance from the countershaft 2. The beams after passing throughthe rolls are laid upon the able support. A is preferably provided for taking up the cot in treating beams and similar taking them to the bath, immersing them therein and withdrawing them therefrom.

pair oftongs or other device such as 4; bperated from the traveling hoist 5 which runs suitable construction for instance by means of movable fire boxes 8, 8 so that the fires may be withdrawn if the temperature of the bath gets too high-and may be reapplied when the temperature gets too low. In this connection it will be noted that as the steel beamsor other members are of a considerably higher temperature than the bath they will have a tendency, while the process continues, to impart sufiicient heat. to. the'bath to maintain it above the mini mum temperature without the use of the fires 8, 8. If however, the quantity of material being treated is operated intermittently, it will be necessary to apply'heat to the bath in order to maintain the desired minimum temperature. The parafiin will penetrate any slight scale which may formbetween the time the steel leaves the rolls and enters the bath. The members are left in the bath if necessary, a

short time say-fr0m one to five seconds and this process is cent thereto so that any excess of parafiin aratus for carrying theinv'en beams as they come from the finishing rolls,

metal arranged in a convenient location heated in any suitable manner for instance small or the process Patented June 2, 191a.

ture of the bath should be maintained subfloor 3 or any, other suitsuitable form of conveyer In the form shown this consists of a suitable on a rail 6. The bath is contained in a tank superior when a to unite two or are then Withdrawn and laid upon a suitable rack or support such as the inclined trough 9 from which the excess of paraflin may run back into the tank so as to avoid wasting ofthe paraflin and unnecessary depletion of the bath.

I have found that the process operates more successfully and that the product is certain per cent. of some carbonaceous material such as lampblack is mixed with the paraffin in the bath. The proportion of lampblack employed may vary from say-2 ounces to the gallon of parafiin up to say-a pound of lampblack to a gallon of paraffin depending upon the results desired. The lampblack gives body to the coating and durability so that it is able to withstand a greater amount of wezgr and tear without materially injuring the coating or exposing the surface of the metal. A Y

percentage of diatomite may also be employed either with the lampblack or supplementary thereto and in about the same proportions. Diatomite is practically a nonconductor of heat and will enable the product to withstand a great amount ofabrasion. The diatomite may be applied in the bath with the lampblack or in a separate bath, either as a substitute for the whole or a part of the lampblack in some cases or supplementary thereto in other cases. I have also found that when steel beams or other members have been treated with paraffin and lampblack as herein described an especially efiective result is obtained by dusting the coated steel with diatomite while the steel is hot and the paraflin is still soft. 'As the steel and paraffin cools the diatomite becomes strongly embedded in the parafin.

When beams or steel members are used in building constructions it is often necessary rivets. In practising my process parafin is a temperature above and allowing the steel, to drain more parts by means of applied to each end of each rivet as the rivet is being finally upset and while hot and by this means every part of the metal surface is coated and such spaces as exist between the rivets and the beams are filled with the waxm The parafiin is practically unafiected by acids or the weather and not subject to oxidation and when applied as herein set forth prevents any corrosion or oxidation of the steel. Even when the surface of paraffin is worn off there is a suflicient quantit of the paraflin left in the pores of the steel to prevent any corrosion other than the most minute and superficial.

Steel, coated according to my invention may be palnted if desired and ordinary paint will adhere thereto.

\Vhat I claim is The process of protecting steel from corrosion by means of parafiin which consists in immersing uncoated steel in an open bath of melted paraflin the temperature of the steel being considerably above the melting point of the paraffin and below the ignition point of the paraffin, maintaining the temperature of the parafiin substantially constant, leaving the steel in the bath for a suflicient length of time to permit the steel to be cooled somewhat and absorb the paraflin into the steel, and withdrawing the steel from the bath while the steel is still at the melting point of the paraffin and cool outside the bath.

Signed at New York, in the county of New York and State of New York this 13th day of October A. D. 1910.

EDWARD MAY CAFFALL.

Witnesses:

CORNELIUS W. WICKERSHAM, Ron'r. S. ALLYN. 

